JPH0322749Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an illumination device for a projector, and more particularly to an illumination device for an optical tracing grinder.

For example, in the optical copying grinding machine shown in FIG. 1, the light beam from the shading irradiation light source lamp 1 passes through the lens group 3 and the dustproof glass 5 and irradiates the material to be ground 7 and the grinding wheel 9 to remove the shadows. dustproof glass 1
1, half mirror 13, reflective mirror 15, 17, 19
, one of the plurality of selectable magnifying lens groups 21
The large reflecting mirror projects the shadow 29 of the material to be ground and the shadow 31 of the grinding wheel, or the light from the reflected image irradiation light source lamp 33 is transmitted to the grinding wheel 9 by the half mirror 13 described above. , is irradiated onto the upper surface of the material to be ground 7, and its positive image is projected onto the screen 27 of the projector 25 in the same manner as the shadow projection described above, thereby performing optical tracing grinding.

Conventionally, incandescent bulbs have been used as these light source lamps 1 and 33, but halogen lamps are used because of their stable color temperature characteristics, long life, and small size. is desirable. However, halogen lamps require that the temperature around the halogen lamp be maintained at a relatively high temperature in order to maintain the halogen cycle. However, since optical copying grinders perform highly accurate grinding, if a halogen lamp is simply installed as a light source, the temperature inside the grinder will rise and the thermal effect cannot be ignored. Therefore, in the past, it has been considered difficult to use a halogen lamp as a light source for an optical copying grinder.

The present invention was devised in view of the above-mentioned conventional problems, and an embodiment thereof will be described in detail below based on FIG. 2.

FIG. 2 illustrates the area around the light source lamp 1 for irradiating shadows.

Originally, a halogen lamp had a tungsten filament and halogen gas sealed in highly heat-resistant quartz glass, and when the temperature of the bulb was maintained between 250℃ and 350℃, the filament was released. Tungsten vapor generated at high temperatures combines with the halogen sealed near the tube wall of the halogen lamp to form tungsten halide. When the tungsten halide moves through the tube of the halogen lamp and touches the high temperature of the filament again at the center, it is reduced to metal and adheres to the filament, and the halogen is gasified again, creating a so-called halogen cycle. A characteristic of halogen lamps is that there is no blackening of the glass part due to consumption of tungsten and adhesion of tungsten halide to the inner wall of the bulb, so it is necessary to maintain the bulb temperature within the above-mentioned temperature range.

In FIG. 2, a lamp housing 35 is installed horizontally on a machine frame 37 of an optical copying grinder, and an inner cylinder 41 is fitted into a lamp holding cylinder 39 provided on one side of the lamp housing so as to be slidable and positionable. Four knobs 43 are provided at the left end of the inner cylinder 41, and the position of the bright spot 45 of the halogen lamp 1 can be adjusted and fixed vertically and horizontally.

A lens group 3 is attached to the upper center of the lamp housing 35 to irradiate the irradiated area with light from the halogen lamp 1, and a heat ray absorbing glass 47 is provided on the lowermost surface of the lens group 3 in the vicinity of the halogen lamp 1. be.

The lamp holding tube 3 of the lamp housing 35
On the opposite side of one end of the ventilation tube 9, there are provided an outer ventilation tube 49 and an inner ventilation tube 51, the inner ends of which are relatively close to the halogen lamp 1. An outside air passage is formed in. A lamp housing 35 is located at the right end of the ventilation inner cylinder 51.
In order to discharge the high temperature air inside to the outside, an exhaust fan 53 such as a Sirotskov fan is provided so that the displacement can be adjusted by changing the rotational speed.

Furthermore, a shielding plate 55 is provided between the halogen lamp 1 and the ventilation outer cylinder 49 and ventilation inner cylinder 51 to prevent the air flowing in from the outside air passage from directly hitting the halogen lamp 1. There is.

With the above configuration, when the exhaust fan 53 is operated, the heated air inside the lamp housing 35 is transferred to the ventilation inner tube 51.
The outside air flows into the lamp housing 35 from the outside air passage between the ventilation outer cylinder 49 and the ventilation inner cylinder 51. Therefore, the inside of the lamp housing 35 can be cooled, and the influence of heat due to the heated air inside the lamp housing 35 can be avoided. In addition, since heated air is discharged from inside the ventilation inner cylinder 51 and outside air flows in from the outside of the ventilation inner cylinder 51, even if the temperature of the ventilation inner cylinder 51 increases due to the heated air, , heat transfer to the machine frame 37 is prevented. Furthermore, since the outside air flowing into the lamp housing 35 from the outside air passage is prevented from directly hitting the halogen lamp 1 by the shielding plate 55, the temperature of the halogen lamp 1 does not drop abnormally, and the halogen lamp The cycle can be maintained well.

As can be understood from the above explanation of the embodiments, the gist of the present invention is as stated in the claims for utility model registration. However, it is possible to avoid thermal effects caused by higher temperatures than necessary, and to prevent the temperature of the light source lamp from dropping below the required temperature, even if only temporarily. Therefore, a halogen lamp can be used as the halogen lamp.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the optical system of the optical tracing grinder, and FIG. 2 is a sectional view of the area around the lamp housing of the shadow illumination device of FIG. 1. 1... Halogen lamp, 35... Lamp housing, 49... Ventilation outer cylinder, 51... Ventilation inner cylinder, 5
3...Exhaust fan, 55...Shielding plate.

Claims (1)

[Scope of utility model registration request] A halogen lamp 1 is arranged and provided in a lamp housing 35 attached to a machine frame 37 in an optical copying grinding machine, and a lens group 3 for irradiating light from the halogen lamp 1 to an irradiated part is supported in the lamp housing 35. The lamp housing 35 is provided relatively close to the halogen lamp 1.
The inner end of the ventilation outer cylinder 49 supported by the ventilation outer cylinder 49 is provided close to the halogen lamp 1, and an outside air passage is formed between the ventilation inner cylinder 51 fitted into the ventilation outer cylinder 49 and the ventilation outer cylinder 49. and provided in the ventilation inner cylinder 51,
An exhaust fan 53 is installed to discharge high-temperature air inside the lamp housing 35 to the outside, and is provided between the outside air passage and the halogen lamp 1 so that outside air flowing from the outside air passage directly hits the halogen lamp 1. An illumination device for an optical tracing grinder, characterized in that a shielding member 55 is disposed to prevent this.